1. Field of the Invention
The present invention relates to a disc device in which a disc, such as a compact disc (CD) or a digital versatile disc (DVD), is transported to and positioned at a disc driving section by a transport roller. More particularly, the present invention relates to a disc device which is capable of preventing a disc positioning member from interfering with the rotation of the disc that is being driven.
2. Description of the Related Art
In a disc device for recording information onto and reproducing it from a disc by automatically pulling the disc into the disc device, the disc that is inserted needs to be reliably positioned on a turntable of a disc driving section. In a disc device that can receive, for example, a disc having a small diameter of 8 cm and a disc having a large diameter of 12 cm, it is necessary to position these discs on the same turntable.
Therefore, in such related disc devices, a positioning member which comes into contact with the outer peripheral edge of the disc that is inserted in order to position the central portion of a disc on the turntable is disposed at the back side of the disc driving section. The positioning member is constructed so that, when a disc having a small diameter of 8 cm is inserted, the positioning member is positioned at a location where the outer peripheral edge of the small-diameter disc comes into contact therewith, whereas, when a disc having a large diameter of 12 cm is inserted, the positioning member is moved to a location where the outer peripheral edge of the large-diameter disc comes into contact therewith. Therefore, in general, related disc devices are constructed so that the small-diameter disc and the large-diameter disc are positioned by the same positioning member.
However, in such disc devices including a disc positioning member as mentioned above, it is necessary to use a structure for separating the positioning member from the outer peripheral edge of the small-diameter disc or the large-diameter disc after positioning the central portion of the small-diameter disc or the large-diameter disc at the disc driving section and clamping the central portion of the small-diameter disc or the large-diameter disc to the turntable. When this structure is not provided, the disc that is rotating may become damaged when its outer peripheral edge comes into contact with the positioning member.
In an example of such a structure for separating the positioning member from the outer peripheral edge of the disc after positioning the central portion of the disc at the disc driving section, the positioning member is disposed at a clamp arm including a clamper. In the structure, when the clamp arm rotates in a clamp direction, the path of rotation is made use of to separate the positioning member from the outer peripheral edge of the disc. However, in this structure, it is difficult to sufficiently separate the positioning member from the outer peripheral edge of the disc. In particular, in a thin disc device, since the angle of rotation of the clamp arm is small when clamping the disc, the positioning member cannot be sufficiently separated from the outer peripheral edge of the disc.